C-F6. Multi-VLAN configuration DHCP? C3750-E? CISCO switches, c-f6c3750-e

C-F6. Multi-VLAN configuration DHCP? C3750-E? CISCO switches, c-f6c3750-e

C-F6. Multi-VLAN configuration DHCP? C3750-E? CISCO switches. After VLAN and interface are allocated according to our plan, we need to consider which VLANs need to be configured with the DHCP service. There may be multiple VLANs that need to be configured with the DHCP service.

DHCP Configuration

According to the planning table, we can find that DHCP service is required for all six departments and DHCP service is required for wireless networks. You can set other IP addresses as fixed IP addresses.

① The DHCP configuration method is as follows:

(1)Configure terminalCommand to enter the global configuration mode.

(2)Ip dhcp poolCommand to create a DHCP sub-configuration address pool, usually followed by the VLAN name.

(3)NetworkCommand to configure IP address CIDR blocks for the newly created address pool.

(4)Default-routerCommand to allocate a gateway to the newly created address pool.

(5)Dns-serverThe command assigns an Internet DNS server to the newly created address pool. If you only access the Internet, you can specify two Internet DNS addresses. Separate them with commas (,) or specify the Intranet DNS server.

(6)Ip dhcp exclude-addressThe command is executed after exiting the address pool to set the exclusion address segment. The first and second addresses indicate 1-10, which cannot be used. You can also specify only one address.

② UsableShow runCommand to view the dhcp ip address pool and find the reason why the IP address cannot be obtained.

③ Connect the computer network cable to the first interface of the switch. After a moment, the IP address, gateway, and DNS can be automatically allocated.

4 according to the above method, the VLAN11-16 and VLAN23 are configured with DHCP, after testing, even if the address pool name is not the specified VLan number, can still be allocated to the IP address. It isFind the corresponding VLAN Based on the CIDR block address. Although vlan14 has the same name, route, and DNS as vlan11, the network address is 172.164.0 rather than 172.16.4.0, so that VLAN14 cannot obtain the DHCP address. The modification method is to rebuild it once.

⑤ UsableNo ip dhcp poolCommand to delete the DHCP address pool, so that the corresponding VLAN will not have the DHCP function.

You can also useNo ip dhcp excluded-addressCommand to delete the DHCP exclusion CIDR blocks, which can be obtained by DHCP.